The objective of the 2006 SARE Grant was to begin the process of evaluating mustard in a potato-oats rotation, its potential to improve potato quality while significantly reducing pesticide requirements and improving soil tilth. The study of mustard as part of a potato rotation is projected to take several years as there needs to be an assessment of various cultural practices associated with growing mustard in the Northeast. The cultural practice evaluated in this field trial was to determine the nutrient and fertilization needs of the mustard and mustard’s overall effects on nematodes and other soil pathogens.
We were able to determine some of the cultural requirements of growing the mustard for this purpose in our area. Mustard needs to be planted as early as possible following the oats harvest. It was observed that the mustard appeared to have some weed suppression properties. Perhaps it could be planted immediately following the removal of the oats stubble and forgo the herbicide application thought to be required. It germinates easily but requires adequate moisture in order to grow to its desired height of 3 plus feet. It appears fairly drought tolerant but it just does not grow. Mustard can be successfully planted with a no-till drill but seemed to grow more vigorously when planted on tilled soil. Mustard was successfully grown (in this particular field) to its desired 3 foot height when seeded at 16-17 lbs/acre with an application of 50 pounds of nitrogen/acre along with adequate moisture and sufficient growing season that had abnormally warm temperatures.
We were unable to draw any definite conclusions as to whether or not mustard planted into a potato rotation will have a suppressive effect on soil borne diseases such as verticillium wilt and nematodes.
As is expected, we have more questions than we have answers! It will take several more years of trials and observations in order to draw any definite conclusions as to the benefits of planting mustard in a potato rotation. Hopefully Penn State will continue their mustard trials at the Rock Springs Research Farm and we will be able to compare notes and learn from their research field studies.